Monthly Archives: July 2017

On 5th July, we explored how researchers use an EMG to measure the effort the intercostal muscles exert during breathing. We did four tests on an employee, Galia. The first test was when she was breathing normally with no resistance and her results were recorded on an EMG trace which we extrapolated from and recorded on a table. We carried out the other three tests using different tube lengths (representing different stages of resistance) which were attached to a mask. While collecting the results we found that one of the results did not fit the pattern. To resolve this issue we should have repeated the experiment at least three times. We tried out the equipment on ourselves and found how different factors affected the EMG trace e.g. your posture and slight movements can cause your intercostal muscles to work harder therefore the peaks on the EMG trace are taller. We learnt that testing on children is hard work as they cannot stay still for a long period of time so you need to use certain tactics like putting on Peppa Pig to keep them entertained. We thoroughly enjoyed our experience and learnt valuable knowledge.

On 5th July was our second Student Panel meeting where we were fortunate enough to receive hands-on practical experience in the labs of the Chest Unit at King’s College Hospital! Our main point of interest today was to investigate measurements of inspiratory and expiratory muscle strength. The session started with all the members reintroducing ourselves to one another and speaking about what we study and what we would like to do in the future. It was great to catch up again and meet new members who I didn’t see at our last meeting! I made a load of new friends who gave me valuable tips regarding university and a career in medicine and science. These activities made us all feel very welcome again and very excited for the afternoon!

We were split into three groups depending on what we’d prefer to investigate and I chose to do respiratory muscle testing. My team’s practical was led by Brittany Best who is a current MSc student. Britt was extremely supportive and reassuring which made us find the practical easy and exciting to carry out. She started by teaching us the names and functions of the equipment which we were going to use; these included nose bungs, mouth pieces and a 3-chamber metal valve which we all used at some point of our practical. We also got to pop in to the other group’s rooms and see the cool stuff they were using such as an ECG! In my team, we performed measurements of inspiratory and expiratory muscle strength using the PImax, PEmax and SNIP technique. The PImax was much harder to carry out because we were not used to the equipment but also because it was so unusual to us! This made us think about how difficult a healthcare professional may find it to get accurate data from a patient’s results as patients can often be giggly or even find the unusual technique very awkward and hence will alter their breathing pattern, either purposefully or subconsciously. To obtain results, patients must suck air into their lungs through a mouth-piece. This may sound simple at first, however it quickly challenged our lung muscle ability when my partner was told to close one of the valves. It felt as though my lungs were about to burst because I couldn’t breathe in any air after a certain point due to the valve, but was generating a lot of pressure in my lungs! The SNIP test was much easier to do as it just involved sticking a nose-bung up your nose and breathing regularly with a little twist: give a powerful sniff after every third breath out. Although it isn’t the most fashionable way to gather results, it sure was easier!

Once we all had a chance to take on the roles of both a patient and the scientist, we each analysed our data to see if our values fell into the predicted range values. After a couple of attempts with Brittany reassuring us that it is tough when you’re new to it, we finally got the hang of it! Our values started looking normal as we got more used to the test.

Once we finished our practical, we then all discussed how these tests might be adapted to different patient populations including younger children or those on intensive care. We discussed about how someone on intensive care may not be able to breathe as they usually would and hence more invasive measures would be taken into consideration such as a technique which runs a tube through your nose and down the back of your throat which allows successful results to be collected. We also thought of the difficulties an individual may face due to weakened muscle strength such as those who suffer from motor neurone disease. The team spoke about how hard it must be for somebody’s biceps to always feel very painful and heavy as if a heavy bag was attached on to them! This made us reflect and contemplate about how difficult their home life could be, especially if they lived alone as simple everyday activities such as walking up the stairs could be a challenge to them.

The day was just as expected: very fun and factual! I always enjoy our student panel meetings as each meeting is different from the rest and always involves activities which I have never done before or even knew existed!

Huge thank you again to Dr Vicky MacBean and everybody else who works hard to make all our meetings amazing!

On the 7th of July, as part of the King’s College Muscle Lab Student Panel session, we looked at measuring lung function in two ways, Impulse Oscillometry and Spirometry.

Impulse Oscillometry involved measuring the patient’s tidal breathing over 90 seconds at a 5Hz resistance. We felt the procedure was simple, and once you get used to the noise of the machine, easy to get good readings from. We repeated the examination 3 times, layering the graphs to ensure our results were concordant. We saw a regular trace graph over a 90 second period.

Spirometry was a little more difficult to carry out; we recorded some tidal breathing first to ensure the patient was comfortable and ready, then the patient was asked to inhale as much air as possible into the lungs, then exhale as quickly as possible, all air from their lungs (we encouraged this through shouting as we found the first time round both patients didn’t expel as much air as they could!). This gave us a forced expiratory volume in 1 second value. We also repeated this examination to ensure out results agreed.

Both these tests are good in determining aspects of airway function, with Spirometry also giving FEV1 values and vital capacity, and Impulse Oscillometry giving tidal breathing patterns, however for patients with breathlessness which is a common symptom seen in the chest clinic, these tests could be difficult to carry out and gain accurate results, especially from Spirometry. Also young children may find this difficult to carry out, as it can take a while to get used to breathing with your mouth round the mouthpiece and with a nose clip. Overall it was a good experience to get some practical skills in the clinic and gain some valid result and values to analyse.